Managed to update one of my other blogs to WordPress 2.7 and the latest Thesis theme — went pretty smoothly especially with OpenHook for Thesis. I did a whole new install and imported my old site and had my plugins installed and site configured pretty quickly (couple of hours total).
I very much recommend upgrading if you haven’t already, especially as it looks like it has several SEO features already built in. It also might be a good time to try a new theme that takes advantage of some of the changes in WordPress.
I managed to install WordPress 2.7, didn’t go as smoothly as yours did though, took me 3 attempts, anyway, got there in the end!